pinctrl: renesas: r8a7779: Add PWM pins, groups, and functions

Add pins, groups, and functions for the PWM Timers on the Renesas R-Car
H1 (R8A7779) SoC.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/cea9723e9c3df4b1408750caa38886aac1fab5f7.1679329090.git.geert+renesas@glider.be